1. Technical Field
The present invention relates to image forming devices, and more particularly, to a method and a page printing apparatus that enhances print quality and detection of paper jams by controlling a print engine of the page printing device in response to the detection and transfer of paper within the page printing device.
2. Background Art
The printing operation by which a page printing device, such as a laser printer, prints on a sheet of paper comprises a plurality of subroutines. First, the sheet of paper is drawn into the page printing device. Then, the sheet of paper is appropriately arranged and fed past a printing drum to receive toner. Thereafter, the toner is fused onto the sheet of paper, and finally, the sheet of paper is ejected from the page printing device.
Although conventional page printing devices incorporate sensors for detecting the sheet of paper within the page printing device, these sensors are not used to sequence or time the various sub-routines of the printing operation. That is, most subroutines will be performed at specified times after the printing operation begins by drawing the sheet of paper inside, regardless of whether some delay was experienced in actually grabbing the sheet of paper or whether the pickup roller is operating at a slower than predicted speed, for example. As a result, if there were a delay in grabbing the sheet of paper, for instance, toner on the printing drum will not be properly aligned when it is transferred to the sheet resulting in an improperly aligned transferred image. Therefore, the quality of the final product is undermined. Moreover, the printing drum can be damaged when the toner is not completely transferred to the paper because of the improper alignment.
Another drawback of the conventional page printing device is the failure to detect paper jams effectively. Since the various subroutines of the printing operation occur at specified times after the page printing device begins to draw-in the sheet of paper, even if the sheet of paper jams during alignment, the printing operation still goes forward. Consequently, the toner on the printing drum is again not transferred to the paper resulting in possible damage. Therefore, as is evident above, conventional techniques for operating a page printing device are inadequate and lead to damage of the page printing device.